In general, in a cooking appliance employing microwaves, after closing received foods, when pressing an operation button, a voltage is applied to a high voltage generator. In this case, a commercial voltage applied to the high voltage generator is boosted and the power is applied to a magnetron to generate microwaves, and the microwaves generated by the magnetron are transmitted to a cavity through a waveguide.
At this point, the cooking appliance employing microwaves heats food through frictional heat generated by vibrating the molecules composed of the food by two billions and five million times per second after irradiating the food with microwaves generated from the magnetron.
The cooking appliance employing microwaves is widespread in a home due to various advantages such as ease of the temperature control, cooking time savings, ease of operation and the like.
However, when cooking food employing the microwaves, there are problems that the food is not evenly heated due to a surface deviation of the food and the difference in temperature is generated in the food in part. In addition, there is a problem that a temperature deviation varies when cooking according to the type of food received in the cooking appliance